power loss at high speeds

I have a 95 grand am, 2.3L. When i drive at about 65-70mph, i lose all acceleration for no apparent reason. If I let off gas and then press down again, i usually get power back, only to lose it again. It makes it near impossible to hold a constant speed within 5 or more mph at that speed. The whole ignition module, spark plugs and all, are new. Any suggestions?

Thought is possible vaccuum leak, or leaking throttle body area, allowing air in. Have ya spryaed out the throttle body and butterfly? And have ya tossed some injector cleaner in the tank already?

Quick way to find possible vacuum leaks is

1] spray soapy water solutions on all vacuum hoses and gasket areas, see if the solution bubbles or gets sucked in.

Beyond that, it gets rather involved, and I sure some other of the members may be able to help ya out with thoughts.

2] Use WD-40 instead, if engine rpm at idle changes noticeably, you pinpointing a leak.

My money is on the fuel pump going out the door. How's your power if you accelerate hard from a dead stop? Fuel pump issues are usually apparent under heavy engine loads when fuel needs are high, if the pump is failing and can't supply enough pressure for the engine, the engine will feel like like it's temporarily dieing on you. Food for thought.

Marc

All I can add to this is maybe a professional injector cleaning. It did wonders for my 96 2.4L after the cleaning I have all the power back through all the gears, I can even gain quite a bit in 5th gear.